Flashing Specular Highlights (Car Shader) on stopping StaticMesh

Hi Community!
I built a car shader (based on automotive material) and put it on a car body. Seems to work fine on not moving StaticMeshes. But when the body moves by keyframes and stops there is flashing as you can see here:
https://e1.interdubs.com/r/lugundtrug/?al=GFW5Oj&an=
When I import the car body as skeletalmesh and do the same thing, it´s works totally fine (same settings, temporalAA) .
I assume there is a different way unreal handles rendering of static meshes vs. skeletal meshes.
Due to better/more settings (handling of normals, etc.) on static meshes it would be great to use static meshes, anyway.
Is there a way to fix this problem on static meshes?
thanx